| Number | Date | Country | Kind |
|---|---|---|---|
| 8-000120 U | Jan 1996 | JPX | |
| 8-011375 U | Nov 1996 | JPX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 0573470 | Kerngood | Dec 1896 | |
| 0581921 | Schoeppl et al. | May 1897 | |
| 0844486 | Waterman | Feb 1907 | |
| 0886241 | Norton | Apr 1908 | |
| 0954458 | Patterson | Apr 1910 | |
| 1266219 | Curtiss | May 1918 | |
| 3426400 | Lauro | Feb 1969 | |
| 3892015 | Taylor | Jul 1975 | |
| 4437212 | Stahl et al. | Mar 1984 |
| Number | Date | Country |
|---|---|---|
| 390 312 A | Jul 1908 | FRX |
| 1 541 818 | Oct 1968 | FRX |
| Entry |
|---|
| European Search Report dated May 14, 1997. |